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Isonade (3PP)

Gargantuan monstrosity, chaotic neutral

Armor Class 18 (natural armor)
Hit Points 222 (12d20 + 96)
Speed swim 100 ft.

30 (+10) 14 (+2) 26 (+8) 6 (-2) 18 (+4) 8 (-1)

Saving Throws Str +14, Con +12, Wis +8
Skills Athletics +14, Perception +8
Damage Immunities ability damage/drain
Senses darkvision 90 ft., passive Perception 18
Languages understands Aquan and Elvish, but cannot speak
Challenge 14 (11,500 XP)

Special Traits

  • Atmospheric Immunity. The isonade can comfortably exist at any level of the sea and suffers no penalties at any depth.
  • Magic Resistance. The isonade has advantage on saving throws against spells and other magical effects.
  • Water Breathing. The isonade can breathe only underwater.
  • Innate Spellcasting. The isonade’s innate spellcasting ability is Wisdom (spell save DC 16). It can innately cast the following spells, requiring no material components:


  • Multiattack. The isonade makes one tail slap attack and one bite attack.
  • Bite. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 42 (5d12+ 10) piercing damage and the target is grappled (escape DC 20). If the target was already grappled from a previous bite, it’s also swallowed whole (see below).
  • Tail Slap. Melee Weapon Attack: +14 to hit, reach 15 ft., one target. Hit: 31 (6d6 + 10) bludgeoning damage.
  • Breach. The isonade leaps out of the water to crash down onto a target with devastating effect. The isonade must move 30 feet in a straight line toward its target before jumping. When jumping, the isonade travels up to 30 feet through the air before landing. Any creature occupying the space where the isonade lands takes 76 (12d10 + 10) bludgeoning damage and becomes submerged 10 feet below the surface of the water. Targets that make a successful DC 20 Strength saving throw take half damage and are not submerged, but are moved to the nearest unoccupied space. Boats and structures are not immune to this attack.
  • Swallow Whole. When the isonade’s bite attack hits a target grappled from a previous bite attack, the target is also swallowed. The grapple ends, but the target is blinded and restrained, it has total cover against attacks and other effects outside the isonade, and it takes 36 (8d8) acid damage at the start of each of the isonade’s turns. An isonade can have two Large, four Medium, or six Small creatures swallowed at a time. If the isonade takes 40 damage or more from a swallowed creature in a single turn, it must succeed on a DC 20 Constitution saving throw or regurgitate all swallowed creatures, which fall prone within 10 feet of the isonade. If the isonade dies, a swallowed creature is no longer restrained by it and can escape by using 20 feet of movement, exiting prone.


The isonade’s gargantuan thrashing tail is lined with cruelly hooked barbs, and it delights in destruction. When it approaches a coastal village, its tail shoots high into the air from beneath the waves, and it smashes all ships, docks, and nets in its path.


Coastal Destroyer. The isonade is a beast of destruction, sweeping away entire islands and villages. It wrecks seaside communities with battering winds and carves coastlines with its powerful magic. Though not very intelligent, it singles out a community and tries to lure residents into the waves with its animal messenger ability, sending gulls bearing confused riddles, grand promises, and eerie noises to the townsfolk.

Ocean Sacrifices. When coastal villagers suffered from a hurricane or tsunami, they fell back on folklore and blamed the stirrings of the dreaded isonade. To some, appeasing a leviathan such as this makes sense. Some say that a degenerate group seeks to draw the beast forth by sailing from sight of land and dumping a long chain of bound and screaming sacrifices into the lightless depths of the sea.

Enormous Age and Size. The isonade is more than 45 feet long. The beast’s age is unknown, and many coastal bards tell some version of the legend-some believe it is the last of its kind, others believe that a small group of isonade remains.

Section 15: Copyright Notice

Tome of Beasts. Copyright 2016, Open Design; Authors Chris Harris, Dan Dillon, Rodrigo Garcia Carmona, and Wolfgang Baur.